The partially completed histogram and the partially completed table show the times taken, to the nearest second, for a group of people to complete a puzzle.

| Time (seconds) | Frequency |
|---|---|
| 1 – 4 | 2 |
| 5 – 8 | 12 |
| 9 – 10 | 8 |
| 11 – 15 | |
| 16 – 20 | 3 |
Complete the table.
Complete the histogram
One of the participants is selected at random. Estimate the probability that this participant completed the puzzle in under 10 seconds.
121 exam-style questions on OCR (MEI) A Level Maths 2.2 Data Presentation and Interpretation, covering 2.2.1 Types of data and standard diagrams, 2.2.2 Area in a histogram is proportional to frequency, 2.2.3 Cumulative frequency diagram, 2.2.4 Describe frequency distributions, 2.2.5 Samples and theoretical distributions, 2.2.6 Interpret a scatter diagram, 2.2.7 Distinct sections and outliers in scatter diagrams, 2.2.8 Correlation and causation, 2.2.9 Select or critique data presentation techniques, 2.2.10 Measures of central tendency, 2.2.11 Simple measures of spread, 2.2.12 Variance and standard deviation, 2.2.13 Outliers, 2.2.14 Cleaning data, and 2.2 Data Presentation and Interpretation. Each one has a worked solution and a mark scheme showing where the marks go.